Using kelseyhightower/envconfig after code review

test/upgrade/prober/configuration.go

@@ -19,10 +19,8 @@ import (
 	"bytes"
 	"fmt"
 	"io/ioutil"
-	"os"
 	"path"
 	"runtime"
-	"strings"
 	"text/template"
 
 	"github.com/wavesoftware/go-ensure"
@@ -120,17 +118,3 @@ func (p *prober) compileTemplate(templateName string, brokerUrl *apis.URL) strin
 	ensure.NoError(tmpl.Execute(&buff, data))
 	return buff.String()
 }
-
-func envflag(name string, defaultValue bool) bool {
-	if value, ok := os.LookupEnv(name); ok {
-		valid := []string{"true", "yes", "enable"}
-		value = strings.ToLower(value)
-		for _, candidate := range valid {
-			if value == candidate {
-				return true
-			}
-		}
-		return false
-	}
-	return defaultValue
-}

test/upgrade/prober/prober.go

@@ -19,17 +19,13 @@ import (
 	"testing"
 	"time"
 
+	"github.com/kelseyhightower/envconfig"
 	"github.com/wavesoftware/go-ensure"
 	"go.uber.org/zap"
 	testlib "knative.dev/eventing/test/lib"
 	"knative.dev/eventing/test/lib/resources"
 )
 
-const (
-	ServingUseFlag         = "E2E_UPGRADE_TESTS_SERVING_USE"
-	ServingScaleToZeroFlag = "E2E_UPGRADE_TESTS_SERVING_SCALE_TO_ZERO"
-)
-
 var (
 	// FIXME: Interval is set to 200 msec, as lower values will result in errors: knative/eventing#2357
 	// Interval = 10 * time.Millisecond
@@ -68,15 +64,18 @@ type ServingConfig struct {
 }
 
 func NewConfig(namespace string) *Config {
+	servingConfig := ServingConfig{
+		Use:         false,
+		ScaleToZero: true,
+	}
+	err := envconfig.Process("e2e_upgrade_tests_serving", &servingConfig)
+	ensure.NoError(err)
 	return &Config{
 		Namespace:     namespace,
 		Interval:      Interval,
 		FinishedSleep: 5 * time.Second,
 		FailOnErrors:  true,
-		Serving: ServingConfig{
-			Use:         envflag(ServingUseFlag, false),
-			ScaleToZero: envflag(ServingScaleToZeroFlag, true),
-		},
+		Serving:       servingConfig,
 	}
 }
 

test/upgrade/prober/configuration_test.go → test/upgrade/prober/prober_test.go

@@ -23,33 +23,38 @@ import (
 	"github.com/stretchr/testify/assert"
 )
 
-func TestEnvflag(t *testing.T) {
-	envname := "TestEnvflag"
+type envValue uint
+
+const (
+	EnvFalse envValue = iota
+	EnvTrue
+	EnvUnset
+)
+
+func TestNewConfig(t *testing.T) {
+	envname := "E2E_UPGRADE_TESTS_SERVING_USE"
 	suite := []struct {
-		env          string
-		envSet       bool
-		defaultValue bool
-		out          bool
+		env envValue
+		out bool
 	}{
-		{"", false, true, true},
-		{"", true, true, false},
-		{"yes", true, false, true},
-		{"y", true, false, false},
-		{"y", true, true, false},
-		{"true", true, false, true},
-		{"true", true, true, true},
-		{"enable", true, false, true},
-		{"enabled", true, false, false},
+		{EnvFalse, false},
+		{EnvTrue, true},
+		{EnvUnset, false},
 	}
 	for _, s := range suite {
-		t.Run(fmt.Sprintf("env(%t)=%q,def=%t", s.envSet, s.env, s.defaultValue), func(t *testing.T) {
-			if s.envSet {
-				assert.NoError(t, os.Setenv(envname, s.env))
+		t.Run(fmt.Sprintf("env=%v,out=%t", s.env, s.out), func(t *testing.T) {
+			if s.env != EnvUnset {
+				val := "false"
+				if s.env == EnvTrue {
+					val = "true"
+				}
+				assert.NoError(t, os.Setenv(envname, val))
 				defer func() { assert.NoError(t, os.Unsetenv(envname)) }()
 			}
-			result := envflag(envname, s.defaultValue)
+			config := NewConfig("test-ns")
 
-			assert.Equal(t, s.out, result)
+			assert.Equal(t, s.out, config.Serving.Use)
+			assert.True(t, config.Serving.ScaleToZero)
 		})
 	}
 }